The Synthesis Of N-heterocyclic Organic Inhibitors And Study On Their Inhibitory Effects

Since benzotriazole(BTA) had been used as an effective inhibitor for copper in 1940's,many N-organic inhibitors have been developed and applied to chemi-engineering, transportation and oil industry fields widely. Recently imdazoline inhibitors have become the focus of the organic inhibitors. Their potential applications are optimistic due to their properties of low pollution to environment and low toxicity, low expenditure and high efficiency.In this paper, two types of inhibitors have been synthesized , including a series of imidazolyl compounds and a pyrazoline compound. Imidazolyl inhibitors have good soluble property in water and lower expenditure than those of references reported at the same experimental conditions and the same inhibitory effects. The immersion time synthesized compound reaches the expected effects is shorter than those of compounds. Synthesized pyrazoline inhibitor is a new inhibitor that hasn't been reported. It has good inhibitive effect in experimental corrosion systems, and shows better inhibitory efficiency when it mixes with thiourea.This article contains three parts:(1) The first section is a review of the recent development. This part contains simple introduction of the applications of the inhibitors, means of synthesis, mechanism of inhibitive function and methods of studying their inhibitory effects.(2) In the second section, N-Imidazolyl ethyl acetate have been synthesized. Their inhibitive effects for copper in NaHCO3 and Na2SO4 solutions have been studied by polarization curves an AC impedance measurements. The results from experiments showed this type of inhibitors have good effects at lower expenditure .The behavior of absorption on the surface of electrode has been discussed elementarily. The results revealed their absorptions on the surface of metal electrode followed Langmuir isothem. Obtained data of Δ Ga showed their absorptions on the surface of the metal are relative stable.(3) In the last part of this paper, a new pyrazoline compound has been synthesized from 1,3-dipole body reaction. Using electrochemical methods and traditional weight loss method, its inhibitory effects has been studied in different corrosion systems .The results of experiments reveal efficiency of this inhibitor has culmination with increased expenditure. Even higher expenditure, its inhibitive effect decreases. Following , the inhibitive function type changes. Using the results from weight loss method, the rate equation and kinetic parameter had been derived. The synergistic effect between pyrazoline compound and thiourea at high temperature is better than the one at low temperature.